A Masters of the Universe drawing hangs in a frame above the desk in the Capitol Hill office of Alabama senator Jeff Sessions. It stands out among dozens of pictures of his three children and seven grandchildren. The protagonist of the comic-book series, He-Man, is depicted mounted atop his heroic lion, Battle Cat. His muscles are bulging; his sword is thrust into the air. Battle Cat’s mouth is open, his fangs exposed. They are a formidable pair.

A small gold plaque sits below the drawing in the same frame. Etched on it are a portion of the remarks Sessions delivered on the Senate floor in June 2007, two days before the comprehensive immigration-reform bill championed by President George W. Bush and several prominent Republicans was defeated in the Senate. Sessions led the opposition to that bill, and his efforts were among the reasons for its unexpected collapse. “No one small group of people have a right to meet in secret with special-interest groups and write an immigration bill and ram it down the throat of this Senate,” he told his colleagues. “I oppose it. It is not right.”

The artwork was a gift from Cindy Hayden, Sessions’s former chief counsel on the Senate Judiciary Committee, after the 2007 bill was defeated. Sessions called the “small group” that had hashed out the legislation — the politicians, political strategists, and special-interest groups — the “masters of the universe.”

It’s one of his favorite political put-downs. He refers to the CEOs and corporate interests that support amnesty for illegal immigrants as the “masters of the universe in glass towers and suites.” Politicians like John McCain and Lindsey Graham, who have repeatedly tried to push a path to citizenship through Congress, are the “Washington masters of the universe.” Economists, too, are masters of the universe, and former Federal Reserve chairman Ben Bernanke was the “master master.”

Sessions, 67, is a low-profile guy. Though he is not well known nationally, he has for years now been the instrumental force in quashing repeated attempts to pass comprehensive immigration reform. He has a gentle, almost grandfatherly quality, but he doesn’t shy away from combat. He derided the 2007 bill as “no illegal alien left behind”; in a single press conference, he blasted it as a “colossal error,” an “absolute scandal,” and a “fiscal disaster.” He declared: “Good fences make good neighbors.” All of this prompted the Washington Post’s Dana Milbank to call him the “Lou Dobbs of the Senate.”

By the time Sessions was done, on the eve of the Senate vote, calls from the bill’s opponents had shut down the Capitol switchboard. “People were sending bricks through the mail and saying, ‘Use this to build a wall,’ that sort of thing,” he says.

When he was elected to the Senate in 1996, Sessions had no special interest in immigration but, as a career prosecutor, he says the 2007 bill, which would have granted amnesty to the millions of illegal immigrants already in the United States, “just went against my understanding of what law in America was about.”

Sessions grew up in the rural town of Hybart, Ala., where his family ran a country store and, he has said, he learned “the value of hard work and being honest.” He was a Republican even when the South was strongly Democratic. At Huntingdon College in the late 1960s, he was involved with the GOP, and in his senior year he became chairman of the campus chapter of the Young Republicans.

Even before he came to Washington he had spent much of his career in public service, first as a U.S. attorney in Mobile and then as state attorney general. In 1986, when Sessions was 39, President Reagan nominated him to the federal district court in Alabama.

Sessions has always been willing to take on unpopular fights. As U.S. attorney, he prosecuted a group of African-American civil-rights activists for voter fraud, and his nomination prompted charges of racism from local and national officials. Colleagues at the Department of Justice accused him of racism, too, and the late Democratic senator Ted Kennedy warned that he would be a “throwback to a shameful era.” A black colleague and even a local black journalist testified on his behalf. Ultimately, his nomination was defeated. In an unusual turn of events, Senator Howell Heflin, a conservative Democrat who was expected to support his fellow Alabamian, bucked tradition and cast the deciding vote against him.

Sessions ran for the Senate in 1996 after serving two years as state attorney general and got some revenge: He won the seat held by the retiring Heflin. His victory was important for the GOP, too, as part of Alabama’s political realignment and that of the South more broadly. In 1994, Republicans had won the governorship and several other statewide offices. The 1996 elections tested the permanence of those victories, and Sessions’s triumph helped to consolidate the GOP’s gains.

Sessions says that proponents of comprehensive immigration reform, which would address many of the thorny immigration issues facing the country in a single bill rather than in smaller pieces, began redoubling their efforts on June 8, 2007, the day after a Bush-backed bill to bring it about was defeated. To the rest of us, it wasn’t until the day after Mitt Romney’s defeat in the 2012 presidential election that a new immigration bill began to look not just realistic but inevitable. Three days after the election, former George W. Bush aide Mark McKinnon opined, “The best thing about Republicans’ losing is that it will likely force them to cut an immigration deal.” An NBC News headline declared, “GOP resistance to immigration reform could be a casualty of 2012 election.” The Washington Post explained that “the GOP needs to do immigration reform — now.” The Republican National Committee, in its postmortem election report, came to the same conclusion.

A year and a half later, the landscape looks much different. House majority leader Eric Cantor is widely considered a casualty of the immigration issue. And, with Central American children flooding over the southern border, comprehensive immigration reform is, for the time being, all but dead.

More than any other national figure, Sessions is responsible for that turn of events. As the Senate debated the proposal of a group of eight senators — known as the “Gang of Eight” — for comprehensive reform last year, and then as the House toyed with passing it in various incarnations throughout the spring, Sessions’s office served as Ground Zero for the opposition. His staff circulated scholarly studies on Capitol Hill, sent dozens of policy memos to sway ambivalent lawmakers, and relentlessly hassled reporters about the perceived biases in their coverage.

Sessions himself met privately with Republicans in both houses of Congress to persuade them of his views. He also broadcast them in public, taking the Senate floor more than any other lawmaker last year. He spoke for a total of 39 hours, more even than did his colleagues Ted Cruz and Rand Paul, who made national headlines for staging hours-long filibusters. “Without Sessions, I see that amnesty probably would’ve been rammed through,” says radio talk-show host Laura Ingraham, who undertook her own crusade to scuttle the legislation.

Sessions opposes not only providing a path to citizenship for illegal immigrants — many Republicans are against that — but also raising the level of legal immigration. The Gang of Eight’s bill would have markedly increased it, and Sessions was one of the few voices on Capitol Hill arguing that even legal immigration hurts Americans, particularly when the economy is weak and unemployment high.

He has cast himself as a Beltway champion of the middle class, and his message of economic populism is part of a broader attempt to revitalize it. For Sessions, the issue of immigration illustrates better than anything else the divide between the ruling class — the “masters of the universe” — and working-class Americans, with the vast majority of CEOs and business owners favoring reform that, as he sees it, would deal a blow to America’s poor and middle-class workers. He has time and again cited Congressional Budget Office findings that increased immigration lowers wages overall but particularly for the poor. And, though many Republicans have called for allowing high-skilled immigrants into the U.S., particularly in the fields of science, technology, engineering, and math, Sessions has repeatedly drawn attention to statistics suggesting we have more than enough.

So when, less than two months after Romney’s loss, Florida senator and Republican rising star Marco Rubio made it clear he would take the lead in negotiating an immigration-reform proposal with Democrats and the Obama administration, Sessions prepared for battle. Rubio had nearly all of the major financial forces in the GOP behind him; Sessions had history on his side.

He compares the efforts of the pro-reform crowd to a highly orchestrated presidential campaign: “They had exceedingly capable political consultants, they had pollsters to ask the right questions to get the best possible polling numbers, they had TV advertisements, they had rock-star Republicans supporting it, and they felt the train couldn’t be stopped,” he says.

According to the Sunlight Foundation, business and political groups spent more than $1.5 billion between 2008 and 2012 on pro-reform lobbying. Norm Coleman’s American Action Network aired ads on Fox News urging viewers to call Rubio to “thank him for keeping his promise, and fighting to secure the border.” Americans for a Conservative Direction, led by former Mississippi governor Haley Barbour, ran ads calling on viewers to “stand with Marco Rubio to end de facto amnesty.” Americans for Prosperity, a nonprofit group funded by the Koch brothers’ donor network, moved its 2013 conference from Washington, D.C., to Orlando, Fla., and featured Rubio as the keynote speaker. It was the rare issue, says Ingraham, on which the Left and the Right were “completely in cahoots with one another.”

As the legislation took shape, Sessions tried to slow it down in part by drawing attention to the swiftness with which some lawmakers were trying to move it through the Senate. Lawmakers had had two and a half weeks to read the 844-page bill when Judiciary Committee chairman Patrick Leahy scheduled it for a markup. “The only thing I don’t think we want is delay just for delay’s sake,” New York senator Chuck Schumer, one of the bill’s sponsors, said at a committee hearing in late April 2013. Schumer’s strategy, says a Sessions aide, was “to move faster than the truth can travel.”

At the same committee hearing, Sessions gave Schumer a reason for delay. He pointed to an article in the Christian Science Monitor noting that even those involved in crafting the legislation didn’t know exactly how many new immigrants it would allow into the country. He went on to read from the text of the bill to illustrate why it was difficult for some to parse. “The discretionary authority under clause one i may not be used to waive” — he paused, right hand in the air — “roman numeral one, sub-paragraph b, c, d 2, i, e, g, h, or i of section 212 a-2, then, roman numeral two, section 212 a-3, then, roman numeral three, sub-paragraph a, c, d, e of section 212 a-10.” His staff, he told his colleagues, had been working for days “trying to decipher this gobbledygook.” Flashing a smile, he looked at Schumer and said that he’d do his best to be ready to vote on the legislation. “But count me as a, a bit of a protest.”

As the bill moved through the Senate, Sessions used details like these to embarrass its supporters. His efforts were aimed not at them but at the few senators who hadn’t yet made up their minds and, even more important, at the dozens of undecided Republicans in the House of Representatives, which would ultimately decide the bill’s fate. Sessions likes to refer to “true facts,” and he says he felt a “duty to try to educate people on what I thought were the true facts.”

Senator David Vitter was a key ally, and together they plotted legislative strategy. The Louisiana Republican, Sessions says, is “extremely effective in understanding Senate procedures,” and he raised questions about the Gang of Eight’s commitment to securing the border when he forced the Senate to vote on, and reject, an amendment to the bill that would have prohibited legalization before the implementation of a biometric border-check-in system. In April, the duo exasperated Democrats again when Vitter wrote, and Sessions raised on the Senate floor, an amendment to a resolution honoring the late Latino union organizer Cesar Chavez: Vitter noted Chavez’s support for a “secure Southern border” and “enforcement of our immigration laws.” That put New Jersey’s Robert Menendez, who had introduced the resolution, in an awkward position as he objected to the amendment.

The Gang of Eight’s bill passed 68 to 32. Its supporters had hoped for 70 yea votes. “It was wounded when it got to the House, wasn’t any doubt about that,” Sessions says.

The events that unfolded over the next few months didn’t help it. On July 2, the Obama administration quietly announced in a blog post that it would delay for a year the implementation of the Affordable Care Act’s employer mandate. With that, Vitter says, skepticism among Republicans that the president could be trusted to enforce the proposed immigration legislation “went on steroids.” When House members returned from their July 4 recess, says one Republican congressman, “anybody who opposed amnesty-first-type legislation could simply say, ‘Look, if he’s not going to enforce a core part of his namesake legislation, what makes you think he’s going to enforce anything that we pass?’”

Nonetheless, July was filled with talk about whether House leaders would use a conference committee to resolve their disputes with the Senate over the bill. On her radio show, Laura Ingraham sought to prevent them from doing so. Her interviews with GOP House members, regardless of the topic, ended with the same question: “Will you go to conference on immigration, yes or no?” She also made a presidential endorsement. “Jeff Sessions, we need Jeff Sessions for president,” she said. “Really, is there anyone out there who is better than Jeff Sessions on any of these issues?”

When lawmakers left Washington for their annual August recess, Sessions sent House Republicans home with a memo. Dated July 29, 2013, and addressed to “Republican colleagues,” it sought to refute the political and economic arguments in favor of comprehensive immigration reform. Republicans lost the 2012 election not because Mitt Romney won too few Hispanic votes, he said, but because the GOP “hemorrhaged support from middle- and low-income Americans.” While many Republicans had argued that an influx of immigration would aid American businesses, Sessions asked, “What about the needs of workers?” He urged them to embrace a “humble and honest populism.”

The argument took. Among House members, the political argument was particularly effective. After the 2012 election, says one Republican congressman, “it was almost just accepted that you’d do the amnesty and then you’d do better amongst Latino voters.” Ronald Reagan and George W. Bush did relatively well among Hispanics: Reagan won 37 percent of the Hispanic vote in 1984, and Bush won 40 percent in 2004. Though both supported amnesty, neither campaigned on the issue. In the first election after Reagan signed the 1986 immigration bill, which legalized over 2 million people, George H. W. Bush earned just 30 percent of the Hispanic vote. John McCain, who had for years championed comprehensive immigration reform, did little better.

Eventually even Republican supporters began to concede there would be no political payoff. In a closed-door meeting, says the congressman, “Paul Ryan eventually said immigration reform won’t help us win more votes, but ‘this is something we need to do.’”

By the new year, House leaders had decided to scrap the Senate bill entirely. But opponents of amnesty like to refer to comprehensive immigration reform as a “zombie issue” — one that time and again springs back to life — and the House leadership decided to sell their colleagues on a set of immigration principles, including a path to citizenship, unveiled shortly before their January retreat at a golf resort in Cambridge, Md.

On January 28, the day before they decamped from D.C., Sessions sent a 30-page memo to House Republicans. He said that the principles unveiled by House leaders resembled in every important way what he referred to as the “Senate Democrat / White House plan.” Complete with a table of contents that catalogued the “myths” propagated by the bill’s supporters, Sessions argued in footnote-full and chart-filled detail against the claims put forward by House leaders. The memo also included a “chartbook” on the adverse economic impact of mass immigration.

“Lots of members rebelled against the principles,” says a House member who was in on several private discussions. The congressman says that when they were discussed in a closed-door meeting of the Republican conference back in Washington, Boehner addressed the room and said, “Look, I got the message.”

In early February, both Boehner and Senate minority leader Mitch McConnell said they couldn’t see an immigration deal happening, but the issue popped up again in April when the Wall Street Journal reported that Boehner had told donors at a Las Vegas fundraiser he was “hell-bent” on passing an immigration bill in 2014. The speaker finally threw his hands up at the end of the month. “Every time the president ignores the law like the 38 times he has on Obamacare,” he said, “our members look up and go, ‘Wait a minute.’”

Sessions characterizes Eric Cantor’s primary defeat in June and the humanitarian crisis unfolding on the southern border as “exclamation points” on his efforts over the past year. The latter has proved disastrous for the Obama administration and for those who supported the Gang of Eight bill, offering a national illustration of the catastrophic impact of lax immigration laws. “A few years ago,” says a Republican congressman who opposes amnesty, “people like me could predict what was going to happen. Now we don’t have to predict, we just point.”

Congress has yet to come up with any viable legislation to stem the tide of illegal immigrants and young children pouring over the border. The House last week passed a symbolic bill that increases funding to deploy National Guard troops to the border and closes a loophole in a 2008 law, making it easier to deport the unaccompanied minors entering the country. The Democratic Senate blocked the bill and jetted off on vacation.

The result of Sessions’s efforts is that the president is now left with just one option to accomplish his goal: implementing an executive order that would grant amnesty to between 6 and 9 million illegal immigrants. It won’t be couched in the feel-good language of the Gang of Eight bill, and it will come with enormous political costs.

The denouement, if you can call it that, offers an important political lesson: Intensity matters. It is said more often of the fight over gun control, but it is true of all political battles. Opponents of amnesty, Sessions chief among them, proved more passionate and energetic than their adversaries. For over a year, Sessions and his staff owned the immigration issue every day. Though supporters of the legislation, both in 2007 and 2013, peddled a narrative of inevitability, Sessions helped nurture and give expression to the skepticism of many Republican voters whose voices weren’t represented by the CEOs and lobbyists who helped craft the bill.

And he won, both times. That might not make him a master of the universe, but it makes him one of the most important assets that the Right has.

— Eliana Johnson is a national reporter forNational Review Online. This piece is adapted from an article that appeared in the August 11, 2014, issue of National Review.